You've been incredibly rude to him, you've effectively just told him to go away and stop bothering you, and you've sold him a broken app. He isn't wrong - there's a bug in your app that you're refusing to fix, so if you get a negative review you absolutely deserve it.
Saying no just really makes some people un-happy.
You didn't say no. You CC's in the guy's HR department to try and get him some sort of disciplinary action in his job. That's a long way past saying no.
You really need to stop doing support yourself and hire someone who's actually good at it.
You've been incredibly rude to him, you've effectively just told him to go away and stop bothering you, and you've sold him a broken app. He isn't wrong - there's a bug in your app that you're refusing to fix, so if you get a negative review you absolutely deserve it.
Saying no just really makes some people un-happy.
You didn't say no. You CC's in the guy's HR department to try and get him some sort of disciplinary action in his job. That's a long way past saying no.
You really need to stop doing support yourself and hire someone who's actually good at it.